In order to solve the problems of difficult test, high cost and long cycle in the development of large-scale airborne negative pressure isolation system, the simulation analysis of negative pressure response characteristics is carried out around various aviation conditions such as aircraft ascending, leveling and descending, especially rapid decompression, based on the computational fluid dynamics (CFD) method. The results showed that the isolation cabin could achieve -50 Pa pressure difference environment and form a certain pressure gradient. The exhaust air volume reached the maximum value in the early stage of the aircraft's ascent, and gradually decreased with the increase of altitude until it was level flying. In the process of aircraft descent, the exhaust fan could theoretically maintain a pressure difference far below -50 Pa without working; Under the special condition of rapid pressure loss, it was difficult to deal with the rapid change of low pressure only by the exhaust fan, so it was necessary to design safety valve and other anti-leakage measures in the isolation cabin structure. Therefore, the initial stage of aircraft ascent is the key stage for the adjustment and control of the negative pressure isolation system. By controlling the exhaust air volume and adjusting parameters, it can adapt to the change of low pressure under normal flight conditions, form a relatively stable negative pressure environment, and meet the needs of biological control, isolation and transport.
Aircraft ; Computer Simulation ; Aviation/instrumentation* ; Humans ; Hydrodynamics ; Air Pressure ; Equipment Design ; Pressure

Peyronie's disease (PD) is a connective tissue disorder characterized by abnormal collagen deposition in the tunica albuginea, leading to penile curvature, pain, and erectile dysfunction. This study aimed to evaluate the outcomes of a combined treatment protocol incorporating collagenase clostridium histolyticum (CCH), vacuum erection device, and tadalafil. A retrospective analysis was conducted on 99 male patients with PD treated at the Department of Urology, Hamad Medical Corporation (Doha, Qatar) between January 2018 and January 2020. Patients received 4-8 CCH injections alongside vacuum therapy and daily tadalafil (5 mg). The baseline mean penile curvature of 49.0° improved by an average of 21.4% post-treatment. Erectile function scores also increased significantly, with a mean improvement of 2.3 points on the International Index of Erectile Function. Minor complications were observed in 15 patients, while 13 were dissatisfied with treatment, with six opting for surgery. The modified protocol demonstrated significant improvements in penile curvature and erectile function with minimal complications, offering a safe, cost-effective alternative to traditional intensive treatments.
Humans ; Male ; Penile Induration/therapy* ; Tadalafil/therapeutic use* ; Retrospective Studies ; Microbial Collagenase/administration & dosage* ; Middle Aged ; Vacuum ; Treatment Outcome ; Adult ; Penile Erection ; Combined Modality Therapy ; Phosphodiesterase 5 Inhibitors/therapeutic use* ; Aged ; Erectile Dysfunction/etiology*

Vaccination is a crucial strategy for the prevention and control of infectious diseases. Virus-like particles (VLPs), composed of structural proteins, have garnered significant attention as a novel type of vaccine due to their excellent safety and immunogenicity. However, similar to most vaccine antigens, VLPs exhibit insufficient thermal stability, which not only restricts the widespread application of vaccines but also increases the risk of vaccine inactivation. This study aims to enhance the stability and shelf life of VLPs derived from type A foot-and-mouth disease virus (FMDV) by employing vacuum freeze-drying technology. The optimal lyoprotectant formulation was determined through single-factor and combinatorial screening. Subsequently, the correlation between the immunogenicity of the freeze-dried vaccine and the content of FMDV VLPs was evaluated via a mouse model. The stability of FMDV VLPs before and after freeze-drying was further assessed by storing them at 4, 25, and 37 ℃ for varying time periods. Results indicated that the lyoprotectant formulation No.1, composed of 7.5% trehalose, 0.1% Tween 80, 50 mmol/L glycine, 1% sodium glutamate, and 3% polyvinylpyrrolidone (PVP), effectively preserved the content of FMDV VLPs during the vacuum freeze-drying process. The immunization trial in mice revealed that the levels of specific antibodies, immunoglobulin G1 (IgG1), interleukin-4 (IL-4), and neutralizing antibodies induced by freeze-dried FMDV VLPs were comparable to those induced by non-freeze-dried FMDV VLPs. The heat treatment results showed that the storage periods of freeze-dried FMDV VLPs at 4, 25, and 37 ℃ were significantly longer than those of non-freeze-dried FMDV VLPs. In conclusion, the selected lyoprotectant formulation effectively improved the stability of FMDV VLPs vaccines. This study provides valuable insights for enhancing the stability of novel subunit vaccines.
Freeze Drying/methods* ; Animals ; Foot-and-Mouth Disease Virus/immunology* ; Mice ; Vaccines, Virus-Like Particle/chemistry* ; Foot-and-Mouth Disease/immunology* ; Vacuum ; Drug Stability ; Mice, Inbred BALB C ; Viral Vaccines/immunology*

INTRODUCTION

Hysteroscopy is the gold standard procedure for the evaluation and diagnosis of intrauterine pathologies. The optimal time to do hysteroscopy is during the proliferative phase. However, for women with irregular bleeding, the optimal time is unpredictable. Besides pharmacological means, mechanical endometrial preparation could be done.

The objective of this study was to determine the effect of suction curettage on visualization, operative time, fluid deficit, and histopathologic diagnosis among perimenopausal women with abnormal uterine bleeding (AUB) and unprepared endometrium prior to operative hysteroscopy.

Thirty-four (34) perimenopausal women admitted for AUB with unprepared endometrium for operative hysteroscopy who consented to participate were recruited and randomly divided into two groups: 18 women had suction curettage done prior to operative hysteroscopy and 16 women had operative hysteroscopy done alone. The following data were obtained for each group: (1) improvement in clarity (i.e., visualization of fundus and both tubal ostia), (2) operative time from entry to withdrawal of the resectoscope (measured in minutes), (3) fluid deficit, and (4) final histopathological diagnosis. P 

Women who underwent suction curettage prior to operative hysteroscopy had improved visualization (72.2%, P < 0.001), shorter operative time (29.06 ± 7.06 min vs. 35.5 ± 7.2 min, P = 0.013), no difference in fluid deficit (P = 0.276), and the histopathologic diagnosis (P = 0.470).

Suction curettage prior to operative hysteroscopy among perimenopausal women with AUB and unprepared endometrium improved visualization and shortened operative time without affecting fluid deficit and histopathologic diagnosis.

The purpose of this study was to establish a suitable method for extracting cerebrospinal fluid (CSF) from C57BL/6 mice. A patch clamp electrode puller was used to draw a glass micropipette, and a brain stereotaxic device was used to fix the mouse's head at an angle of 135° from the body. Under a stereoscopic microscope, the skin and muscle tissue on the back of the mouse's head were separated, and the dura mater at the cerebellomedullary cistern was exposed. The glass micropipette (with an angle of 20° to 30° from the dura mater) was used to puncture at a point 1 mm inboard of Y-shaped dorsal vertebral artery for CSF sampling. After the first extraction, the glass micropipette was connected with a 1 mL sterile syringe to form a negative pressure device for the second extraction. The results showed that the successful rate of CSF extraction was 83.33% (30/36). Average CSF extraction amount was (7.16 ± 0.43) μL per mouse. In addition, C57BL/6 mice were given intranasally ferric ammonium citrate (FAC) to establish a model of brain iron accumulation, and the CSF extraction technique established in the present study was used for sampling. The results showed that iron content in the CSF from the normal saline control group was not detected, while the iron content in the CSF from FAC-treated group was (76.24 ± 38.53) μmol/L, and the difference was significant. These results suggest that glass micropipette vacuum technique of CSF sampling established in the present study has the advantages of simplicity, high success rate, large extraction volume, and low bleeding rate, and is suitable for the research on C57BL/6 mouse neurological disease models.
Mice ; Animals ; Vacuum ; Mice, Inbred C57BL ; Cisterna Magna ; Brain ; Cerebrospinal Fluid

INTRODUCTION: There has been a global decrease in operative vaginal deliveries, with a marked shift towards the vacuum extractor. However, little is known about the trends in operative vaginal delivery in Singapore. METHODS: A retrospective study was conducted on all operative vaginal deliveries performed from 2012 to 2017 at Singapore General Hospital (SGH). Maternal outcomes in terms of postpartum haemorrhage and obstetric anal sphincter injuries were compared between forceps- and vacuum-assisted deliveries. Neonatal outcomes in terms of neonatal intensive care unit (NICU) admission and clinically significant neonatal events were compared. The instrument preference of obstetricians was analysed. RESULTS: A total of 906 consecutive operative vaginal deliveries were included in the study, comprising 461 forceps- and 445 vacuum-assisted deliveries. The rate of operative vaginal delivery was maintained at approximately 10% from 2012 to 2017. Neonatal cephalohematomas were more common after vacuum-assisted deliveries. Other maternal and neonatal outcomes did not differ significantly between the two groups. Clinically significant neonatal events were mostly due to shoulder dystocia, whereas all cases of NICU admissions were not directly related to the mode of delivery. Obstetricians' choice of instrument appeared to reflect personal preference and was not affected by the year of graduation. CONCLUSION The rates of neonatal and maternal morbidity were low at SGH. Overall instrument use of forceps and vacuum was balanced, and proficiency in both was demonstrated by all operators. Operative vaginal delivery remains an essential skill in facilitating safe vaginal delivery, which should be maintained to keep Caesarean section rates in check.
Infant, Newborn ; Pregnancy ; Humans ; Female ; Cesarean Section ; Retrospective Studies ; Vacuum Extraction, Obstetrical/adverse effects* ; Hospitals, General ; Obstetrical Forceps/adverse effects* ; Delivery, Obstetric

Objective: To establish a high performance liquid chromatography method for the determination of misoprostol in workplace air. Methods: From February to August 2021, the misoprostol in the workplace air was collected by glass fiber filter membrane, and theeluent was separated by C18 liquid chromatography column, determined by UV detector, and quantified by external standard method. Results: The quantitative lower limit of misoprostol determination method was 0.05 μg/ml, and the lowest quantitative concentration was 1.4 μg/m(3) (calculated by collecting 75 L air sample). The concentration of misoprostol has a good linear relationship between 0.05 to 10.00 μg/ml. The relative coefficient was 0.9998. The regression equation of the standard working curve was y=495759x-45257. The range of average recovery rates were from 95.5% to 102.8%. The intra-assay precision of the method was 1.2%-4.6%, and the inter-assay precision was 2.0%-5.9%. The samples could be stored stably for 7 days at 4 ℃. Conclusion: The high performance liquid chromatography method for the determination of misoprostol has high sensitivity, good specificity and simple procedure of sample pretreatment. It is suitable for the detection of misoprostol in the workplace air.
Chromatography, High Pressure Liquid/methods* ; Misoprostol/analysis* ; Air Pollutants, Occupational/analysis* ; Workplace ; Chromatography, Liquid

OBJECTIVE: This study aimed to investigate the association of ambient PM_2.5 exposure with blood pressure (BP) at the population level in China. METHODS: A total of 14,080 participants who had at least two valid blood pressure records were selected from the China Health and Retirement Longitudinal Survey during 2011-2015. Their long-term PM_2.5 exposure was assessed at the geographical level, on the basis of a regular 0.1° × 0.1° grid over China. A mixed-effects regression model was used to assess associations. RESULTS: Each decrease of 10 μg/m³ in the 1 year-mean PM_2.5 concentration (FPM_1Y) was associated with a decrease of 1.24 [95% confidence interval (CI): 0.84-1.64] mmHg systolic BP (SBP) and 0.50 (95% CI: 0.25-0.75) mmHg diastolic BP (DBP), respectively. A robust association was observed between the long-term decrease in PM_2.5 and decreased BP in the middle-aged and older population. Using a generalized additive mixed model, we further found that SBP increased nonlinearly overall with FPM_1Y but in an approximately linear range when the FPM_1Y concentration was < 70 µg/m³; In contrast, DBP increased approximately linearly without a clear threshold. CONCLUSION Efficient control of PM_2.5 air pollution may promote vascular health in China. Our study provides robust scientific support for making the related air pollution control policies.
Middle Aged ; Humans ; Aged ; Particulate Matter/analysis* ; Blood Pressure ; Air Pollutants/analysis* ; Follow-Up Studies ; Hypertension/etiology* ; East Asian People ; Environmental Exposure/analysis* ; Air Pollution/analysis* ; China/epidemiology*

Cavernous nerve injury is an important cause of erectile dysfunction (ED). Although protective nerve technology has been widely used in nerve-sparing radical prostatectomy (nsRP), the incidence of ED is still very high after surgery. The purpose of our study was to evaluate erectile function (EF) and penile length in the non-erectile state (PLNES) following scheduled phosphodiesterase 5 inhibitor (PDE5i), vacuum erectile device (VED) treatment, and combination therapy after nsRP. One hundred patients with localized prostate cancer and normal EF were randomized to scheduled PDE5i group, VED treatment group, a combined treatment group, and the control group without any intervention. The International Index of Erectile Function-5 (IIEF-5) scores and PLNES were evaluated after 6 months and 12 months of treatment. Sexual Encounter Profile (SEP-Question 2 and SEP-Question 3) were evaluated after 12 months of treatment. Ninety-one of the 100 randomized patients completed the study. We found that the 5 mg tadalafil once a day (OaD) combined with VED can help improve IIEF-5 scores in nsRP patients after both 6 months and 12 months. VED alone or combined with tadalafil OaD can help patients maintain PLNES. VED combined with tadalafil OaD can improve the rate of successful penetration (SEP-Question 2) after 12 months. There were no significant differences in the return to target EF after 12 months among the groups. No significant correlation was noted between the variables and return to target EF (IIEF ≥ 17), and between the variables and effective shortening of the patient's penis (shortening ≥ 1 cm) after 12 months of intervention.
Erectile Dysfunction ; Humans ; Male ; Penile Erection ; Phosphodiesterase 5 Inhibitors ; Prospective Studies ; Prostatectomy ; Prostatic Neoplasms ; Tadalafil ; Treatment Outcome ; Vacuum

Objective To explore the application value of automatic nucleic acid extractor combined with vacuum concentrator in forensic DNA extraction. Methods Gradient samples of human peripheral venous blood were collected at 40, 80, 120, 160, 200, 240, 280 and 320 fold dilution. The samples of each gradient were treated with no inhibitor, black oil, rust, fruit acid, tin foil and indigo, respectively. The automatic nucleic acid extractor was used for DNA purification and extraction of the above samples. The extracted DNA eluent （6 μL） was taken for amplification directly, and the rest was concentrated by vacuum concentrator. DNA was amplified and examined using the Investigator 26plex QS kit before and after concentration. Results Only gradient samples treated with fruit acid obtained complete STR typing results at 40 fold dilution. The other 5 methods obtained complete STR typing results at 40-160 fold dilution. The results of STR typing after DNA concentration showed that the average peak height and detection rates of gene loci both increased to a certain extent, but the effect was not obvious. Conclusion The automatic nucleic acid extractor has an efficient inhibitor removal ability and high extracting efficiency of DNA. The vacuum concentrator can concentrate DNA samples to a certain extent. Combining the automatic nucleic acid extractor with the vacuum concentrator can improve the examination success rate of forensic materials.
DNA/genetics* ; DNA Fingerprinting ; Humans ; Microsatellite Repeats ; Nucleic Acids ; Vacuum